Lock



Nav. 19? 1940.

A. H. GOLDEN ET Al. v2,222,027

LOCK

Filed Spt. 8, 1938 INVENTORS ATTORNEY (f/Mg Patented Nov. 19, 1940 UNITED sTA'irr-:s

PATENT orric.

LOCK

Application September 8, 1938, Serial No. 2281.968

` 7 Claims.

This invention relates to a pin tumbler cylinder lock, and more particularly to means for preventing the unauthorized rotation of the key plug of such a lock.

Those skilled in the art fully. appreciate that many means have been devised toprevent the picking of pin tumbler cylinder locks. Such means are usually of a character requiring a considerable number of parts, or extremely careful manufacture, so as to increase considerably the cost of the cylinder locks in which they are embodied. Moreover, such means are usually of a character tending to complicate the operation of cylinder locks, so asv to require considerable serv- 1c1ng.

Our invention contributes to a pin tumbler cylinder lock a feature whereby, even though the tumblers of the lock be picked, it is impossible to rotate the key plug a sufficient distance to operate the lock.

More particularly, our invention is drawn somewhat along the lines ofA that disclosed in the patent to Pepper, No. 1,707,992, granted April 2 1929. In the Pepper patent, there is formed in the cylinder an additional driver bore in which there is mounted a locking pin spring. pressed to.- ward the key plug. Should the key Plug be r,o`

tated without the tumblers lined up with the plug periphery, as is the case when the tumblers are picked, the locking pin is forced by its spring into one of the pin tumbler chambers as the key plug is rotated past the pin. To prevent the picking of the locking pin thereafter outwardly of the pin tumbler chamber into which it is pressed, Pepper utilizes an additional deadlocking pin I9 which locks the locking pin in its locked position.

In our invention, we eliminate the additional4 deadlocking pin which is used by Pepper. We are able to accomplish this by having the locking pin interlock with means which areV preferably formed as part of the driver bore surface, as the locking pin moves into the pin tumbler chamber. This interlock prevents backward movement of the locking pin out of the pin tumbler chamber. Preferably, this is accomplished by having the locking pin fo-rmed so that it cants under the influence of its spring, that is, moves angularly under the influence of its spring, as it is pressed into the pin tumbler chamber. As it cants, the locking pin moves into locking relation with a shoulder in the driver bore so as to prevent its being picked back out of the pin tumbler chamber.

In order to make it possible to service the cylinder, should the key plug be rotated and locked by the locking pin, we back up the locking pin spring with a removable plug which is preferably screw threaded into the cylinder. By simply removing the threaded plug, it is possible to removev the locking pin and spring and replace the locking pin in its original position, thus rendering the lock fully operative once again.

We shall now describe a specic form of our invention shown in the accompanying drawing. Before doing so', we should like to point out that we consider this invention of relatively broad scope, and we do not wish to be limited in our monopoly except as is required by the state of the art, including the Pepper patent.

In the drawing, Fig. l is an elevation and partial section of `a cylinder incorporating our invention. Figs. 2, 3 and 4 are sections taken along lines 2 2 of Fig. 1 illustrating the par-ts in various positions.

Referring now more particularly to the draw- 1 1 ing, reference numeral I0 designates a standard type of cylinder lock having a key plug II in which are mounted a series of pin tumblers I2. The pin tumblers I2 cooperate with a series of drivers I3 arranged in driver bores I4 in the cylinder It, the drivers being pressed downwardly into locking position by a series of springs l5, all as is well understood in the art.

In Figs. 2, 3 and 4, there is shown an additional driver bore I6 formed in cylinder I0, and in which isA mounted a locking pin Il having an angular upper surface I 8 against which presses a spring I9 backed up by a removable threaded plug 20. There may be one or more of these bores and locking pins, and they may be posit7 tioned` to cooperate with any of the tumbler chambers of the key plug. If a proper key, shown in section in Fig. 4 and designated by reference numeral 2l, is inserted into the key way of the plug II, all of the pin tumblers I2 will be positioned with their upper ends aligned with the plug periphery, as is clearly shown in Fig. 4. vIithe` key plug be now rotated, it will rotate in the usual way, and one of the pin tumblers I2- will prevent the locking pin Il from being pressed by itsspring into the tumbler chamber in which the tumbler I2 is. maintained.

Should the tumblers I2 be picked and the plug rotated without a key, and to the position of Fig.

3, it is obvious that the spring i9 will press the 1 because of the shape ofthe upper surface I8 of "4 the locking pin I1, pressure of the spring i9 will cause the locking pin to cant, or move angularly as in Fig. 3, at the same time that it moves into the chamber of the pin tumbler I2.

As is quite obvious, the exterme edge 22 of the pin il interlocks with the shouldered portion 23 of the driver bore I6, and with the parts in this position, it is impossible through pressure on the pin tumbler I2 to force the locking pin l1 back into its bore, that is, into its position of Fig. 4. Because of this, it will be impossible to rotate the key plug Il either in a clockwise or counter clockwise direction from the position of Fig. 3, and the lock will be inoperative.

As we have already indicated generally, it is possible to remove the threaded plug 2i), and thereby obtain access to the locking pin Il and its spring I9. Locking pin I1 may then be released from its position of Fig. 3, and the entire combination reset so that it may operate once again as in Figs. 2 and 4.

We now claim:

1. In a pin tumbler lock of the type having a key plug, and tumblers and drivers adapted to move in tumbler and driver bores and to be set with their parting lines along the plug periphery, said lock having an additional driver bore spaced angularly from the usual bores and adapted for alignment with one of the tumbler chambers, a locking pin in said driver bore and a spring in said bore pressing said pin downwardly in the direction of said tumbler chamber whereby if the key plug isv rotated without the tumbler in said chamber positioned with its upper end surface on the plug periphery, said pin will be pressed into said tumbler chamber, said additional driver bore being formed to interlock with an integral part of said locking pin after said pin enters said tumbler chamber whereby to prevent retractive movement of said pin out of said tumbler chamber thereafter.

2. In a pin tumbler lock of the type having a key plug, and tumblers and drivers adapted to move in tumbler and driver bores and to be set with their parting lines along the plug periphery, said lock having an additional driver bore spaced angularly from the usual bores and adapted for alignment with one of the tumbler chambers, a locking pin in said driver bore and a spring in said bore pressing said pin downwardly in the direction of said tumbler chamber whereby if said key plug is rotated without the tumbler in said chamber positioned with its upper end surface on the plug periphery said pin will be pressed into said tumbler chamber, and a locking surface on said additional driver bore with which an integral part of said locking pin interlocks as it moves into said tumbler chamber whereby to prevent retractive movement of said pin out of said tumbler chamber thereafter.

3. In a pin tumbler lock of the type having a key plug, and tumblers and drivers adapted to move in tumbler and driver bores and to be set with their parting lines along the plug periphery, said lock having an additional driver bore spaced angularly from the usual bores and adapted for alignment with one of the tumbler chambers, a locking pin in said driver bore and a spring in said bore pressing said pin downwardly in the direction of said tumbler chamber whereby if said key plug is rotated without the tumbler in said chamber positioned with its upper end surface on Vthe plug periphery said pin will be pressed into said tumbler chamber, an angular surface on said locking pin against which said spring presses whereby to cant said locking pin in its bore as it is pressed into said tumbler chamber, and a surface of said bore with which said pin interlocks as it cants whereby to prevent retractive movement of said pin back out of said tumbler chamber.

4. In a pin tumbler lock of the type having a key plug, and tumblers and drivers adapted to move in tumbler and driver bores and to be set with their parting lines along the plug periphery, said lock having an additional driver bore spaced angularly from the usual bores and adapted for alignment with one of the tumbler chambers, a locking pin in said driver bore and a spring in said bore pressing said pin downwardly in the direction of said tumbler chamber whereby if said key plug is rotated without the tumbler in said chamber positioned with its upper end surface on the plug periphery said pin will be pressed into said tumbler chamber, a surface on said locking pin against which said spring presses designed so that said spring cants said locking pin as it is pressed into said tumbler chamber, and means with which said pin interlocks as it cants whereby to prevent retractive movement of said pin back out of said tumbler chamber.

5. In a pin tumbler lock of the type having a key plug, and tumblers and drivers adapted to move in tumbler and driver bores and to be set with their parting lines along the plug periphery said lock having an additional driver bore spaced angularly from the usual bores and adapted for alignment with one of the tumbler chambers, a locking pin in said driver bore and a spring in said bore pressing said pin downwardly in the direction of said tumbler chamber whereby if said key plug is rotated without the tumbler in said chamber positioned with its upper end surface on the plug periphery said pin will be pressed into said tumbler chamber, said locking pin being smaller in diameter than at least a portion of its bore and formed so as to cant in said driver bore as it is moved under spring pressure into said tumbler chamber, and a surface of said bore with which an integral part. of said pin interlocks as it cants whereby to prevent retractive movement of said pin back into said driver bore.

6. Ina pin tumbler lock of the type having a keyplug, and tumblers and drivers adapted to move in tumbler and driver bores and to be set with theirparting lines along the plug periphery, said lock having an additional driver bore spaced angularly from the usual bores and adapted for alignment with one of the tumbler chambers, a locking pin in said driver bore and a spring in said bore pressing said pin downwardly in the direction of saidtumbler chamber whereby if said key plug is rotated Without the tumbler in said chamber positioned with its upper end surface on the plug periphery said pin will be pressed into said tumbler chamber, said locking pin being formed so as to cant in said driver bore as it is moved under spring pressure into said tumbler chamber, and means with which said pin interlocks as it cants whereby to prevent retractive movement of said pin back into said driver bore.

7. In a pin tumbler lock of the type having a key plug, and tumblers and drivers adapted to move in tumbler and driver bores and to be set with their parting lines alongl the plug periphery, said lock having an additional driver bore spaced angularly from the usual bores and adapted for alignment with one of the tumbler chambers, a locking pin in said driver bore and a spring in said bore pressing said pin downwardly in the direction of said tumbler chamber whereby if said key plug is rotated without the tumbler in said chamber positioned with its upper end surface on the plug periphery said pin will be pressed int-o said tumbler chamber, said locking pin lying partially in a portion of said additional driver bore which is substantially the `same in diameter as said locking Din, and partially in a portion of said bore larger in diameter, said locking pin 10 moving into said larger diameter portion as it moves under spring pressure into the tumbler chamber, said locking pin having an angular surface against which its spring presses whereby it cants when in said larger diameter portion to interlock with a shoulder formed between the two portions of said driver bore whereby to prevent retractive movement of said pin back out of said tumbler chamber. l

CHARLES LEDIN.

ABRAHAM H. GOLDEN. 

